The disclosed embodiments relate to a brake device for a railway vehicle that includes at least one service brake cylinder having at least one service brake piston actuated by a pressurized medium.
Conventionally, a brake device of the type in question is known from EP 0 674 116 B1. It is provided with a parking brake device comprising symmetrical cam actuation, in which cams having an involute contour arranged on a shaft are in engagement on both sides of a piston rod tube with rollers that are mounted on the piston rod tube in such a way as to be rotatable about a common rotational axis. Since a parking brake device of this kind has to produce large parking brake forces owing to the comparatively high weight of railway vehicles, a parking brake device of high efficiency with minimum frictional forces is desired.